Like all big corporations Amazon's mission is usually to achieve more (revenue) with less costs. Duh.

In the past decade or so Amazon also has done a dive into turning books (probably kindle ones) into series. I mean uber 5 fat chapters, or a series, instead of one book. I totally get it for the writers POV especially if writing is a significant contributor to income.

From the reader's POV this doesn't always work overtime. Also if the production fees/costs don't kill you and you have a spare hubby floating around with a nice pleasant deep Euro-trash voice, (or your voice) you might want to check out Amazon's audible property, but the ROI there is even trickier.